Typically, printed circuit modules include conductive traces consisting of a layer of printed ink having fine conductive particles embedded therein. The ink is rendered conductive by physical contact between the conductive particles therewithin, and electronic components are connected to contact areas of the conductive traces to effect an electrical connection therebetween. Such printed circuit modules are used in various areas of electronic technology. The circuit modules can be interchangeable or installed permanently in electronic devices and equipment. Rigid circuit carrier substrates, for example, typically consist of an epoxy resin construction, with glass fiber or glass fiber inserts. Flexible circuit carrier substrates are, for example, films of polyester resin or the like. Electronic components include any components usual in electronics used in conjunction with printed circuits. The electronic components can perform various functions or sophisticated circuitry, and may include functional parts as well as simple junctions or connecting bridges.
In printed circuit modules known in practice, the conductive traces consist of printed ink layers which include fine metallic particles, such as silver or nickel embedded therein. However, metallic silver, though very conductive, is not very hard, and both silver and nickel are affected by and corrode under the influence of the surrounding environment. When using such materials, harmful changes in conductivity often cannot be avoided. It is therefore usually necessary to coat the conductive traces, and more particularly, the contact areas of the traces, with a protective layer of carbon, for example. However, prior to the electrical connection to a corresponding contact surface of an electronic component, the protective layer of carbon must be removed or otherwise be rendered ineffective in order that an adequate electrical connection can be made. These secondary procedures can be time-consuming and costly.